exam 3 Flashcards
what constitutes the core of a virus?
proteins (enzymes) genetic material (DNA and RNA)
what constitutes the covering of a virus?
capsid (protein)
envelope (lipid envelope that surrounds capsid, not always present)
what is the potential genetic material found in viruses?
purines- adenine & guanine
pyrimidines- thymosin & cytosine, uracil replaces thymosin in RNA
what effect do viruses have on cells?
cell destruction- start to see symptoms
cell alteration- does not interfere with cell activity, recognizes as foreign and attacks
cellular transformation- does not respond to normal growth control- does not stop growing (tumors)
shapes of viruses
bullet shaped spherical helical icosahedral complex
what is a bacteria virus
bacteriophage
steps in viral infection cycle
- adsorption- attachment to cell, specific proteins on virus attach to specific proteins on cell wall
- penetration- enveloped virus- fusion of membrane, envelop of virus fuses with cell membrane. naked virus- endocytosis, comes around cell, cell now in a vesicle
3 .release of viral genetic material- uncoat capsid to release genetic material from cytoplasm (endocytosis- enzymes and pH break down capsid) - steps in nucleic acid replication and protein synthesis- virus comes into cell and makes copies of self to make more of virus. need proteins to make genetic material
- assembly of viral particle- need to make capsid around genetic material
6.release of infectious viral particle- enveloped-lyse, naked- buds off
how to make copies of Double stranded or single stranded DNA
- More DNA
- Make mRNA (transcription)
- Make proteins (translation)
how to make copies of Positive ss RNA
(don’t have to make mRNA because already there)
- Make more copies of positive single stranded RNA (mRNA)- genetic material (transcription)
- Make proteins (translation)
how to make copies of Negative ss DNA
- Have to make it positive
- Make -ssRNA (genetic material)
- Make mRNA (transcription)
- mRNA Makes proteins (translation)
how to make copies of Double stranded RNA
- Make copies of dsRNA (genetic material)
- Make mRNA (transcription)
- mRNA makes proteins (translation)
Poxiviridae enveloped or naked?
enveloped
Poxiviridae genetic material
ds DNA
ds DNA viruses
poxiviridae
herpesviridae
adenoviridae
papovaviridae
diseases in poxiviridae
smallpox
monkey pox
Molluscum contagiosum
smallpox symptoms
rash, pussy lesions, blisters
smallpox transmission
respiratory
close face to face contact, bodily fluids
fomites
smallpox prevention
- variolation- mild form injected into skin
- use cowpox (vaccinia)- for military because they are scared it could be used as a bioweapon
- quit giving it to people because cannot get from wild
how did smallpox get eradicated?
- ring vaccination method, vaccinate those around infected
- easy to administer and no refrigeration needed
how long is smallpox contagious for?
until blister falls off
what are the side effects of the smallpox vaccine
sore arm, fever, body aches
should an immunocompromised receive the vaccine for smallpox?
no it could cause them to get disease
does the smallpox vaccine require the virus?
no, uses another virus called vaccinia
monkeypox transmission
close contact
bite of an animal
does monkeypox infect humans? what are some of the symptoms?
yes, rash, pussy blisters
preventative measure for monkey pox
use vaccinia virus
wash hands
Molluscum contagiosum symptoms
pearly lesions (virus stays in upper layer of skin)
Molluscum contagiosum transmission
contact with lesion
fomite
treatment for Molluscum contagiosum
freeze, pop of lesion with scalpal
-do have oral drugs and ointment to reduce
herpesviridae diseases
herpes simplex 1 herpes simplex 2 varicella-zoster epstein barr kaposi's sarcoma
herpesviruses enveloped or naked?
enveloped
herpesviruses genetic material
ds DNA
herpesvirus is considered a latent disease. what does this mean?
stays dormant, comes out during a flare up. virus gets into dna and stays there forever
symptoms of HSV1
fever blister on lip
transmission of HSV1
oral secretions, sores on lip
where does HSV1 remain latent?
trigeminal nerve
treatment for HSV1 fever blisters?
Acyclovirs-
Valacyclovir (pill)
penciclovir (ointment)
symptoms of HSV2
painful lesions on genitals
transmission of HSV2
sexually
are condoms effective against preventing infection of HSV2?
no, they may not cover it because you dont need to see blisters to be infectious
treatment for HSV2
Acyclovirs to surpress
- valacyclovir helps prevent lesions
- topical has no benefit
varicella (chickenpox) symptoms
starts as itchy rash, blister lesions form on trunk face and limbs
transmission of chickenpox
close contact with those infected with chickenpox or shingles
complications of chickenpox
can cause infection from scratching (meningitis, encephalitis, pneumonia)
treatment of chickenpox
- varivax vaccine (attenuated form)
- acyclovirs
- do not take aspirin (Reyes’ syndrome)
symptoms for zoster (shingles)
painful blister lesions on trunk, seeping chickenpox virus
what is the requirement for having shingles?
must have had chickenpox before
treatment for shingles
- valcyclovir, methyl glyoxal (Manuka honey)
- vaccine: zostavax (65% effective), shingrix (>90% effective)
how are chickenpox and shingle related?
shingles can cause chickenpox
Epstein Barr (mononucleosis) symptoms
inflamed liver, spleen, throat, lymph nodes
what percent of adult have been infected with Epstein Barr
95%
transmission of Epstein barr
bodily fluids
what is the relationship between Epstein Barr and burkitt’s lymphoma
can get burkitt’s lymphoma from mono
nasopharyngeal carcinoma
kissing disease, drinking out of same glass as someone with mono
burkitt’s lymphoma symptoms
- swelling in lymph region in jaw
- in people who have been exposed to malaria
adenoviridae enveloped or naked
naked
adenoviridae genetic material
ds DNA
what diseases are caused by adenoviridae
common cold, croup, pneumonia, bronchitis, gastroenteritis (diarrhea), conjunctivitis (pink eye)
HHV6
roseola- rash looks like rose
HHV8
kaposi sarcoma-associated herpes virus
transmission of adenoviridae
coughing, sneezing
eating food
fomites
swimming pools
prevention of adenoviridae
wash hands, use tissue when sneeze or cough
papovaviridae enveloped or naked
naked
papovaviridae genetic material
ds DNA
diseases in papovaviridae fam
papilloma virus
polyoma virus
vacuolating virus
symptoms for human papilloma virus
warts, can cause cervical warts which lead to cancer
transmission of papilloma virus
sexually, touching wart
prevention of papilloma
gardasil, must be vaccinated before exposure
polyoma virus
monkey virus- SV40
can cause polio?
maybe cause tumors in humans
vacuolating virus
plant viruses
parvoviridae enveloped or naked
naked
parvoviridae genetic material
ss DNA
disease in parvoviridae
canine parvovirus
B19: fifth disease
symptoms in canine parvoviridae
heart problems in puppies
diarrhea